1. Field of the Invention
The present invention concerns a screw, in particular a self-tapping screw.
2. Description of Related Art
It is known that serrations which usually run in the longitudinal direction i.e. crosswise to the movement of the screw tip as compared with the wood are arranged on the tip of the screw to make threading screws into wood or wood-like material easier. These serrations are also intended to reduce the risk of splits or splintering.
In a known screw of this type (DE 19525732), the serrations for a conical screw tip are in one forming the cone, in other words they run in a longitudinal centre plane contained in the longitudinal axis of the screw.
A screw (EP 939235 A) is also known where several serrations are diagonally arranged and in fact at an inclination angle compared to the longitudinal axis in a range of approximately 15°.